Case manipulator for a palletizer system

ABSTRACT

A case manipulator receives cases from an infeed conveyer and manipulates individual cases or groups of cases and transfers the manipulated cases to a row accumulator platform in a desired and pre-determined orientation and positioned on the accumulator platform to a desired and pre-determined location. The manipulation of individual cases, or groups of cases, is continued in a sequential operation until a complete row is formed on the accumulator platform according to a pre-determined build menu. The case manipulator includes a swing plate pivotal on a first axis and a paddle arm that is attached to the swing plate and pivotal on a second axis that is transverse to the first axis. The invention allows the palletizer to have the next case in a row transferred from the infeed conveyer to the row-build staging area while the case manipulator is operating on an already-delivered case.

TECHNICAL FIELD

The present invention relates to palletizing systems and morespecifically to a case manipulator apparatus and method that is used toinsure that cases delivered to a row building component of a palletizerare delivered in the correct orientation and with the proper spacing.

BACKGROUND

A palletizer is an apparatus that receives and manipulates items, suchas boxes, also called cases, and places the manipulated items on palletsin pre-determined positions and orientations in organized rows, layersand stacks to form a stable stack of boxes arranged on a pallet forshipping. Palletizers are often combined with stretch wrapping machinesthat are either a component of the palletizer assembly itself or aseparate machine. In either case, the stretch wrapping machine overwrapsthe stack of cases that the palletizing machine has deposited on thepallet in order to form a highly stable load that is ready for shippingand which will remain stable throughout the shipping process.

There are innumerable devices for palletizing articles, but described ina very general sense all palletizers receive a sequence of items andmanipulate those items to produce a palletized stack of them. As noted,typically, a completed stack of cases is shrink wrapped as part of thepalletizing operation in order to finalize the stack for shipping.

Stated in very general terms, a typical palletizer receives a series ofitems from an infeed conveyer, organizes the items into one or more rowson a row build conveyer, organizes the rows into layers on a componentsuch as a layer head, and generates a stack of layers on a pallet.Depending on the type of machine, complete rows of cases may betransferred to onto a pallet or a complete layer of items (i.e.,multiple rows of items) may be assembled and transferred at once onto apallet.

Efficient shipping of palletized items calls for efficient stacking ofitems on the pallet to minimize open space within the stack and to helpinsure the stability of the stack to prevent relative movement betweenitems, and ultimately, to insure that the items in the stack arrive attheir destination undamaged. Of course, boxes come in a variety of sizesand many boxes are rectangular with opposed parallel side panels andtherefore have different width and length dimensions. A standard palletis used widely throughout the shipping industry. By varying theorientation and/or pattern of boxes from layer to layer, a stable stackof items may be constructed upon a standard-sized pallet. Accordingly, avariety of “box patterns” have been established for stacking specificbox sizes on standard pallets. By using an established box pattern forgiven rectangular boxes that are to be stacked on a standard pallet, theresult is an efficient and stable stack of the boxes on the pallet thatwill perform well during shipping and handling. Modern palletizers areunder the control of a microprocessor that controls all aspects of thepalletizing operation. Among other things, the controller haspre-determined “build menus” that correspond to box patters and whichare specific to specific box dimensions and pallet load specifications.During operation of the palletizer, the build menu determines how thepalletizer orients and arranges the plural boxes so that the finalizedstack on the pallet is optimally stable.

A common palletizing system comprises several components that worktogether to perform the palletizing operation. Boxes are initiallyplaced on an infeed system that delivers the boxes to a row buildsystem. Often the infeed system includes box turning equipment thatorients individual boxes in the correct orientation relative to adjacentboxes for the specific box pattern that is being used. Rows areassembled on the row build system—each row is a set of plural boxesarranged according to the box pattern as set by the build menu. A row istransferred by one of a variety of methods from the row build system toa layer building station where plural rows are arranged into a layer. Astack is formed by depositing a first layer onto a pallet or slip sheetand subsequent layers are deposited atop the next adjacent lower layer.Layers are added until the stack is complete. Typically, the palletizingoperations at the various stations run simultaneously to the extentpossible to increase throughput efficiency. As would be expected, thereare many variations of the equipment used to palletize, and the generalthemes of operation.

Regardless of the equipment that is being used, palletizing requiresefficiency in design and operation of the device. Among other design andoperational criteria, efficiency is often one of the most importantconsiderations. In many applications, time is most critical and apalletizer that more quickly organizes an incoming series of items intoa palletized stack of items represents an advantage by increasingthroughput and thus greater production levels and economic efficiency.

That said, different operations have different requirements forpalletizing equipment. A high speed, high throughput palletizer might beappropriate for a high volume manufacturer but a lower speed systemwould be just as appropriate for a lower volume manufacturer. As wouldbe expected, the higher speed palletizing systems tend to be moreexpensive than the lower speed system. Therefore, there is a need in themarketplace for many different palletizing systems that meet the varietyof needs of the consumers of these systems.

It will be appreciated that mishandling of boxes in the palletizingprocess should be minimized as part of an efficient operation and that apalletizing system must be designed to avoid delivery of boxes to thepalletizer in an incorrect orientation. For example, a box that isdelivered to a palletizer in the incorrect orientation for the specificbox pattern that is being used will cause formation of a defectivelayer. This results in shut down, or at least significant slowdown ofthe entire palletizing sequence and operator intervention is oftenrequired in order to correct the orientation of the mis-oriented box.Unfortunately, delivery of such “out of bounds” boxes—that is, boxesthat are either in the incorrect orientation or which are otherwiseimproperly placed—to palletizing systems continues to be a significantproblem and is the cause of much slowdown in palletizing operations.Moreover, any time operator intervention is required to correct out ofbounds situations presents a safety concern for workers.

There is a need therefore for a palletizing system that insures deliveryof boxes to the equipment in the correct orientation and spacing forwhatever box pattern is being used. At the same time, there is a needfor a palletizing system that meets the economies of the consumer'sspecific needs.

The present invention comprises systems that address the shortcomings ofprior systems and is directed to a case manipulator that accurately andprecisely positions cases on a row build system according to apre-determined build menu. The case manipulator according to the presentinvention is capable of receiving cases from an infeed conveyer,manipulating individual cases when received from the infeed conveyer,transferring the manipulated cases to a row accumulator platform in adesired and pre-determined orientation and positioned on the accumulatorplatform to a desired and pre-determined location. The manipulation ofindividual cases, or groups of cases, is continued in a sequentialoperation until a complete row is formed on the accumulator platformaccording to the build menu. The invention allows the palletizer to havethe next case in a row transferred from the infeed conveyer to therow-build staging area while the case manipulator is operating on analready-delivered case. These and other benefits are described herein.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be better understood and its numerous objects andadvantages will be apparent by reference to the following detaileddescription of the invention when taken in conjunction with thefollowing drawings in which the case manipulator of the invention isfirst shown in the context of an overall palletizing system in order toshow environment, and the invention is then shown in isolation in orderto provide details.

FIGS. 1 through 2 illustrate a complete palletizing system that includesa case manipulator according to the present invention. Specifically,

FIG. 1 is an upper perspective view showing a palletizing system,including the frame elements that support the various components.

FIG. 2 is a top plan view of the palletizing system shown in FIG. 1.

FIG. 3 is a perspective view of selected components of the casemanipulator according to the present invention, illustrating the paddlein the upward position.

FIG. 4 is an end elevation view of the case manipulator shown in FIG. 3,illustrating the paddle in the upward position in solid lines and in thedownward position in phantom lines.

FIG. 5 is a perspective view of selected components of the casemanipulator according to the present invention as shown in FIG. 3 butillustrating the paddle in the downward position.

FIG. 6 is a perspective view of the case manipulator shown in FIG. 5 butillustrating the apparatus from the opposite side from the view of FIG.5.

FIG. 7 is a perspective view of the case manipulator shown in FIG. 6 butshowing the swing plate rotated 90 degrees relative to the position ofthe swing plate shown in FIG. 6.

FIG. 8 is a perspective view showing the paddle and swing plate in thesame positions as shown in FIG. 7 and also showing the manipulatorcarriage and track assembly.

FIGS. 9 through 28 are a series of perspective illustrations showingoperation of the case manipulator according to the present invention,and in which the other components of the palletizer have been omittedfor the purpose of clarity. Specifically,

FIG. 9 shows cases being delivered to the case manipulator on an infeedconveyer;

FIG. 10 illustrates the transfer of a case from the infeed conveyer ontothe row accumulator platform by the case manipulator according to theinvention.

FIG. 11 is similar to FIG. 10 and shows one possible step in the processof using the case manipulator to transfer and position a case on the rowaccumulator platform.

FIG. 12 shows a possible next sequential operation relative to FIG. 11.

FIG. 13 is a possible next sequential operation relative to FIG. 12.

FIG. 14 is continues the possible next sequential operational steprelative to FIG. 13.

FIG. 15 continues the operational sequence and illustrates a completedrow of cases positioned by the case manipulator on the row accumulatorplatform.

FIG. 16 illustrates the row accumulator platform moving verticallyrelative to the infeed conveyer to begin the process of transferring acomplete row of cases to downstream components such as the layer head.

FIG. 17 illustrates operation of the case manipulator according to theinvention to rotate a case as the case is moved from the infeed conveyerto the row accumulator.

FIG. 18 shows a possible next sequential step from the illustration ofFIG. 17.

FIG. 19 continues the sequence from FIG. 18 and shows the casemanipulator moving back to the position in which another case will beacquired for transfer to the row accumulator from the infeed conveyer.

FIG. 20 is a possible next sequential step from FIG. 19.

FIG. 21 continues the sequence of steps from FIG. 20.

FIG. 22 is a possible next sequential step from FIG. 11.

FIG. 23 is a possible next sequential step from FIG. 22.

FIG. 24 is a possible next sequential step from FIG. 23.

FIG. 25 is a possible next sequential step from FIG. 24.

FIG. 26 is a perspective view of an alternative apparatus fortransporting rows of cases, namely, a pick and place clamp system thatmay be used with the case manipulator according to the presentinvention.

FIG. 27 is a side elevation view of selected operative components of thepick and place clamp system shown in FIG. 26, showing the componentswith a case.

FIG. 28 is a perspective view of the alternative apparatus fortransporting rows of cases shown in FIG. 26 but in FIG. 28 the row ofcases has been lifted off the row accumulator by the pick and placeclamp system.

FIG. 29 is a perspective view of yet another alternative apparatus fortransporting rows of cases, in this case a high infeed palletizer thatutilizes a stationary row accumulator platform that may be used with thecase manipulator according to the present invention.

FIG. 30 is another perspective view of the palletizer shown in FIG. 29,illustrating the case manipulator in a different position from the viewof FIG. 29.

DETAILED DESCRIPTION OF ILLUSTRATED EMBODIMENTS

The invention will now be described in detail with reference to thedrawings. Relative directional terms are used at times to describecomponents of the invention and relative positions of the parts. As anaming convention, the ground plane is considered to be the generallyhorizontal surface on which the apparatus of the present invention ismounted. In conventional installations, the apparatus is installed on ahorizontal floor and the upper surface of the various conveyers, rowbuild layers, layer heads, etc. described herein are also horizontal andthus parallel to the ground plane. Other relative directional termscorrespond to this convention: “upper” refers to the direction above andaway from the ground plane; “lower” is generally in the oppositedirection, “inward” is the direction from the exterior toward theinterior of the apparatus, “vertical” is the direction normal to thehorizontal ground plane, and so on. “Upstream” refers to the directionthat is the opposite of the flow of boxes on the system, and“downstream” is the opposite direction—the direction of the flow ofboxes. The articles that are being manipulated on the palletizerdescribed in this specification are standard boxes; in the industry,boxes are also interchangeably referred to as cases and cartons.

Furthermore, in most of the figures used herein some structures areomitted in order to better illustrate selected components andstructures. This includes framing and support structures and the likeused in palletizing systems. Such environmental components are wellknown to those of skill in the art and need not be described or shown inthe figures to understand the invention.

It is to be understood that the case manipulator 10 that is described indetail herein is used as a component of an entire palletizing apparatusthat includes numerous additional systems, including for example a caseinfeed conveyer, a lift deck, a layer head a receiving deck and astretch wrapping station. Some of these components are illustrated inFIGS. 1 and 2, and are described generally below in order to provideenvironment for the case manipulator 10. Versions of the components ofpalletizing systems with which case manipulator 10 may be used aredescribed in detail in, for example, U.S. Pat. Nos. 7,736,120;8,074,431; and 8,257,011, each of which is owned by the assignee of thepresent invention and the disclosures of which are incorporated hereinby this reference.

With reference to FIGS. 1 and 2, and briefly described, the casemanipulator 10 according to the present invention is incorporated into apalletizer system that is identified generally with reference number500. Palletizer system 500 is designed for receiving product that is tobe palletized, for example, cases 12 that are output from a productionor manufacturing operation or from a repackaging operation. Theseso-called production feed areas are located “upstream” of the palletizer500 in terms of product flow. Palletizer 500 includes, among otherthings, a product infeed conveyer 100 that delivers cases 12 from theupstream production feed area in the direction shown with arrow A. Cases12 are moved from the infeed conveyer onto a row accumulator platform 16with the case manipulator 10. Using the case manipulator 10 the casesare manipulated and oriented relative to one another in a desiredorientation according to a build menu that is stored in a controller 14and are transferred onto the accumulator platform 16 to form rows on theaccumulator platform 16. In the embodiment of palletizer 500 shown inFIGS. 1 and 2, the case manipulator 10 operates on the cases 12 to formrows in the direction shown with arrow B, transverse to the direction ofarrow A—that is, the cases are moved by the case manipulator in adirection that is perpendicular to the direction of case travel on theinfeed conveyer. When a complete row of cases 12 has been formed onaccumulator platform 16 by aligning the plural cases along thelongitudinal axis of the platform 16, the platform is moved verticallyso that the row of cases may be transferred to onto a layer head 502,which also may be reciprocated vertically to the desired level fortransfer of the rows thereon. This row-building process continues untilplural rows of cases 12 are transferred onto layer head 502 to thus forma complete layer of cases on the layer head. The layer head 502 is thenmoved vertically so that the complete layer is deposited onto a pallet504, or the underlying next layer that has already been deposited ontothe pallet. The layer head is configured for depositing the layers ontothe pallet in known manners, such as by withdrawing the layer head frombeneath the layer of cases. This process of building layers continuesuntil a complete stack 506 of cases 12 has been formed. The stack ofcases 506, including the pallet 504 (which may be supported on aturntable as part of the palletizer 500), is then moved out of thepalletizer 500 to further processing such as stretch wrapping. It willbe appreciated that the word “case” as used herein refers generically toitems that may be manipulated on a palletizer 500, such as boxes, bags,bundles, trays and other things that may be palletized.

Palletizer 500 in FIGS. 1 and 2 includes a pallet delivery station 508that delivers pallets 504 to the palletizer 500. It will be appreciatedthat there are numerous variations known in the art for making apalletizer 500 and that the apparatus described above is just oneconfiguration of many with which the case manipulator 10 according tothe present invention may be used.

Regardless of the specific types and orientations of components that areused in palletizer 500, each of the components is under the continuouscontrol of a computerized processor or controller that is showngenerally at 14. The controller 14 controls transport conveyers, avariety of motors, sensors and encoders that provide feedback andcontrol information to the controller. Processor 14 is a conventionalmicroprocessor with associated software and systems for completeoperation of the palletizer. Among other things, processor 14 storesplural build menus 18—also referred to herein as “pattern build menus.”As detailed below, each build menu 18 contemplates factors includingcase size, the configuration of cases in rows and orientation of thecases relative to one another, the configuration of rows in layers, andstack height. The build menu 18 thus ultimately defines the number andorientation of boxes in a row, the number and orientation of rows in alayer, and the arrangement and number of layers in a stack.

As another naming convention used herein, all cases shown in thedrawings are identified with the reference number 12. When there is morethan one case 12 shown in a drawing figure, the case that is furthestdownstream in the flow of cases is assigned reference number 12 a, thenext adjacent upstream case is 12 b, then the next upstream case is 12c, and so on. The leading edge of a case 12—that is, the side of thecase that is the forward most side of the case considering the directionthat the case is moving, is identified with a single “prime” symbol—forinstance, 12′. The trailing edge of the same case is identified with adouble “prime” symbol, for instance, the 12″.

Continuing with the general description of palletizer 500, cases 12 arereceived from the production area and delivered to the infeed conveyer100 where individual cases 12 are indexed there along for presentationto the next sequential system of the palletizer, the case manipulator10. As may be appreciated and as is detailed below, cases 12 areoriented on infeed conveyer 100 in a particular orientation. Withreference to FIG. 9, the cases 12 are rectangular and are oriented oninfeed conveyer 100 such that the longest case dimension is parallel tothe direction of movement of the cases along conveyer 100. The buildmenu 18 that is programmed into processor 14 includes data relating tocase size, case orientation, row patterns and case orientation on theconveyer 100 and for the cases in each row, sequential row patterns thatinterfit to form layer patterns, and layer patterns that interrelate toultimately produce a stable stack of boxes on a pallet. As shown in thefigures and as readily recognized, cases 12 are not necessarilysymmetrical in their length and width dimensions. For example, withstandard rectangular boxes the length and width dimensions are not theequal. As such, individual boxes 12 in any given row and any row in alayer may need to be oriented according to the specific predefined buildmenu 18 that takes into account row-by-row variations within a layer,and layer-to-layer variations for adjacent layers on a stack of cases 12deposited on a pallet. An assumption programmed into build menu 18 isthat the individual cases 12 are delivered in a specific orientation oninfeed conveyer 100. In the illustration of FIG. 9, for example, thecases are oriented such that the leading edge 12′ is defined by theshorter width dimension, and thus that the trailing edge 12″ is also theshorter width dimension of the case. Said another way, the longestdimension of case 12 is parallel to the direction of travel alongconveyer 100. The conveyer 100 may optionally include one or moresensors such as electro optical sensor 54 that communicates withcontroller 14 and to detect the position of the leading and trailingedges of a case so that controller 14 can verify the correct orientationof the case on the conveyer. Thus, by detecting the leading edge 12′ andthe trailing edge 12″ with sensors, the length of the case 12 betweenthe edges may be determined. The dimensions of the case 12 areprogrammed into controller 14 and the controller may thus determine theorientation of the case on the conveyer (assuming that as shown in thefigures the case is not square).

The structure of case manipulator 10 will now be described in detailwith reference to FIGS. 3 through 8. But first, as shown in FIG. 9, itwill be understood that case manipulator 10 is adapted to move cases 12from the infeed conveyer 100 onto the row accumulator platform 16. Whenthe infeed conveyer 100 delivers cases 12 in the direction shown in FIG.9, the case manipulator 10 moves the cases in the transverse directionwhen placing the cases onto the accumulator platform 16. It will beunderstood that the infeed conveyer may just as well be orientedrelative to the row accumulator platform that the cases 12 are deliveredto the accumulator in a direction that is parallel to the direction thatthe manipulator moves the cases onto the accumulator.

A backstop plate 20 is located at the downstream limit of infeedconveyer 100 so that cases 12 stop when the leading edge 12′ of a caseabuts the backstop plate 20. The infeed conveyer is preferably aconventional roller conveyer, which may be either driven or non-driven.When a case 12 has its leading edge 12′ abutting the backstop plate 20,the case is in a position that is ready to be acted upon by the casemanipulator 10. Accumulator platform 16 defines a surface that, in ahome position, is positioned adjacent to and at the same vertical levelas the infeed conveyer 100 such that cases 12 on the infeed conveyer maybe slid onto the accumulator platform by the case manipulator 10. Asseen in FIG. 9, the accumulator platform 16 has defines a row buildsurface 22 onto which cases 12 are transferred from infeed conveyer 100.The row build surface 22 is preferably a solid surface on which thecases do not slide without active manipulation—in this way the casesremain where they are positioned on the surface 22 until they areintentionally moved. Surface 22 is thus a relatively high frictionsurface that acts as a dead plate across which cases 12 may be moved.However, once active pushing of a case has stopped the case will notcontinue movement across the surface 22. As noted previously, the rowaccumulator platform 16 is vertically movable so that the verticalposition of the platform may be adjusted to, for example, transfer acomplete row of cases that are positioned on the accumulator platformonto the layer head 502.

Turning now to FIGS. 3 through 8, case manipulator 10 is defined by aswing plate 24 that is mounted to a vertically oriented shaft 26 thathas its lower end 28 coupled to a linkage 30 that allows the shaft to berotated by 90 degrees. The shaft 26 is mounted to a support plate 32 andis attached to the swing plate at the proximate edge of the plate. Apneumatic cylinder 34 is mounted to support plate 32 as shown in FIG. 6and the output shaft 36 has its distal end attached to linkage 30 sothat reciprocal movement of the output shaft 36 under the control ofcontroller 14 causes 90 degree pivoting movement of the swing plate 24about shaft 26. The position of swing plate 24 shown in FIG. 3 issometimes referred to herein as the “home” position or the “firstposition.” The position of swing plate 24 that is shown in FIGS. 7 and 8is the “pivoted” position, or the “second” position. In the pivotedposition the swing plate 24 has been rotated about the verticallyoriented shaft 26 by 90 degrees by action of the pneumatic cylinder 34.As detailed below, the swing plate 24 defines a casepushing/manipulating, major surface 38 that abuts cases 12 and bothpushes the cases and orients them in desired manners. The major surfacemay be covered with a foam pad if desired, for instance, to minimizeabrasion to cases arising out of the contact between the swing plate anda case.

A paddle arm 40 is pivotally mounted at its lower end 42 to ahorizontally oriented shaft 44 that is mounted to the distal or outboardedge of swing plate 24—the shaft 44 is mounted to the swing plate nearthe lower and outer edge of the plate as shown in FIG. 3. A linkage 46that allows the shaft 44 to be rotated by 90 degrees is mounted to swingplate 24 and a pneumatic cylinder 48 is mounted to swing plate 24 asshown in FIG. 3 and the output shaft 50 has its distal end 52 attachedto linkage 46 so that reciprocal movement of the output shaft 50 underthe control of controller 14 causes 90 degree pivoting movement of thepaddle arm 40 about shaft 44. The position of paddle arm 40 shown inFIG. 3 is sometimes referred to herein as the “home” position or the“first position.” The position of paddle arm 40 that is shown in FIGS. 7and 8 is the “pivoted” position, or the “second” position. In thepivoted position the paddle arm 40 has been rotated about the shaft 44by 90 degrees by action of the pneumatic cylinder 48. As detailed below,the paddle arm 40 defines a case pushing/manipulating surface 52 thatabuts cases 12 and both pushes the cases and orients the cases indesired manners.

It will be appreciated by those of skill in the art that the shafts 26and 44 that mount the swing plate 24 and paddle arm 40, respectively,define pivot points for the swing plate and the paddle arm, and thatthere are many known mechanisms other than shafts for defining suchpivot points.

The swing plate 24 and the paddle arm 40 that is attached to it aremounted to a carriage assembly 60 that allows the swing plate and paddlearm to be reciprocally moved and shuttled along the longitudinal axisdefined by the row accumulator platform 16 to thereby move cases on theplatform.

Carriage assembly 60 is defined by a trolley 62, of which support plate32 is one component, and which includes a bottom plate 64 and a sideplate 66 opposite support plate 32. Four wheels 68 are mounted totrolley 62—two wheels 68 mounted to support plate 32 and two wheels 68mounted oppositely to side plate 66. The trolley 62 is mounted in atrack assembly 70 such that wheels 68 ride on rails 72. A pair of guidewheels 74 (only one of which is shown in FIG. 4) are received in a guidechannel 76 so that the reciprocal movement of trolley 62 remains linearat all times.

Movement of trolley 62 is accomplished with a motor 78 that has itsoutput shaft 80 attached to a driven first sprocket 82 at one end of thecarriage assembly 60. A second idler sprocket 84 is mounted at theopposite end of the carriage assembly. A chain 86 has its opposite endsconnected to trolley 62 and extends around the first and secondsprockets 82 and 84 as best seen in FIG. 8. Rotation of output shaft 80of motor 78 causes rotation of driven sprocket 82 and thus movement ofchain 86, and the attached trolley 62. Motor 78 is preferably an encoderfeedback motor that is under the control of controller 14. Andcontroller 14 includes encoder algorithms that correlate with encoderfeedback from motor 78 so that the precise location of swing plate 24,and thus of a case 12 is known. Accordingly, the position of trolley 62and thus swing plate 24 and paddle arm 40 are at all times recognized bycontroller 14.

Operation of case manipulator 10 according to the present invention willnow be explained in detail with reference to the series of figures ofFIGS. 9 through 25 in which the infeed conveyer 100, the row accumulatorplatform 16 and the case manipulator 10 are shown in isolation withoutthe other components of palletizer 500. The arrows in FIGS. 9 through 25show generally the direction of movement of various components duringoperation of the apparatus, as detailed below. It must be pointed outthat in the embodiment and configuration shown in the figures, cases aredelivered to the row accumulator 16 on an infeed conveyer 100 that isoriented so that the flow of cases is perpendicular to the rowaccumulator. As noted previously, the infeed system may just as well beoriented so that cases are delivered in a product flow that is parallelto the orientation of the row accumulator.

Further, and as detailed below, row accumulator 16 illustrated herein isadapted for vertical reciprocal movement to shuttle a row of casesassembled thereon to the next processing component. For instance, when acomplete row of cases 12 has been positioned and assembled on rowaccumulator platform 16 in the desired orientation according to thebuild menu, the row accumulator platform described herein is movedvertically so that the row of cases may be transferred as a row from therow accumulator platform to, for example, the layer head 502. Thetransfer of cases to layer head 502 may be accomplished with a varietyof different mechanism, including pusher bars, puller bars, pick andplace clamp bars, and the like, as known to those of skill in the art.Given that the row accumulator platform 16 is adapted for verticalreciprocal movement, it will be understood that the case manipulator 10described herein is positioned adjacent the row accumulator (and theinfeed conveyer 100) such that the case manipulator is capable ofmanipulating cases 12 that are positioned on the row accumulator 16 andthe infeed conveyer 100 but such that the components do not interferewith one another. The row of cases 12 may be further conditioned asappropriate on with compaction bars and the like if appropriate.

In the preferred embodiment, cases 12 are delivered on infeed conveyer100 in a known and pre-determined orientation—the orientation of thecases on infeed conveyer 100 is programmed into controller 14. Inaddition, case orientation may also be determined and/or confirmed withsensors such as sensor 54 on the infeed conveyer. In this later case,with the case size information stored in the controller 15 at build menu18, the dimension of the case 12 passing by the sensors on the infeedconveyer 100 is known and therefore the orientation of case 12 is known.If a rectangular case such as those shown in FIG. 9 is conveyed past apair of sensors such that the long side of the box is parallel to thedirection of infeed conveyer travel, and the relatively shorter side ofthe box is transverse to the direction of travel, the sensors willdetect a box length. In other words, if the box is situated on theinfeed conveyer 100 so that the leading edge 12′ first trips a sensorbeam and the trailing edge 12″ the controller 14 recognizes box lengthdata and is able to determine that the box is in a given orientation. Ofcourse, if a case is square the orientation of the box on the infeedconveyer 100 is irrelevant.

A complete stack 506 of cases has plural rows and layers of cases andthe number and relative orientations of cases within a row and within alayer will vary depending upon the size and shape of the case. Spacingbetween adjacent cases also may vary. When the cases are non-square suchas cases 12 shown herein such that the length of the case is greaterthan the width, some of the cases are required to be oriented at 90degrees relative to other cases. The build menu 18 includes data thatinforms the required relative positioning of all cases in a stack basedon the desired complete stack information. Controller 14 thus controlsoperation of palletizer 500 to build a complete stack 506 according tothe build menu for the particular cases 12 that are being stacked.

With specific reference now to FIG. 9 the row accumulator platform 16 ispositioned such that row build surface 22 is at the same level as thelevel of infeed conveyer 100—this facilitates smooth transfer of cases12 from the infeed conveyer onto the row accumulator platform 16. InFIG. 9, the swing plate 24 is in the home position and the paddle arm 40is shown in the pivoted position. When the swing plate 24 is in the homeposition the surface 38 of the swing plate acts as a stop for cases 12that are being delivered on the infeed conveyer 100 in the direction ofthe arrow on the cases. When both swing plate 24 and paddle arm 40 arein their respective home positions they are spaced apart and separatedfrom the adjacent edge of the row accumulator platform 16; the surface38 and the analogous surface of the paddle arm are coplanar and in aplane that is spaced from the edge of the row accumulator platform. Asdetailed below, this allows the row accumulator platform to be movedvertically to transfer assembled rows of cases without interference fromthe swing plate and paddle arm. In FIG. 9 there are three cases, 12 a,12 b and 12 c lined up on the infeed conveyer 100. With case manipulator10 in the home position of FIG. 9, the paddle arm 40 is free to movefrom its home position to its pivoted position as shown by the arrow inFIG. 9. In this second, pivoted position, the paddle arm lies adjacent aside of case 12 a.

In FIG. 10 the case 12 a has been moved onto row accumulator platform 16by the case manipulator 10. Specifically, under the control ofcontroller 14 operating motor 78, the trolley 62 has been shuttled inthe direction of the arrow on case 12 a—to the left in the view of FIG.10. Because paddle arm 40 is in the second position and is engaging theside of case 12 a, the case is pushed by the paddle arm along thesurface 22 of the row accumulator as trolley 62 is shuttled—the verticalposition of row accumulator 16 is such that the paddle arm 40 travelsover the accumulator. The case 12 a is pushed on row accumulatorplatform 16 with paddle arm 40 until the case is positioned on theaccumulator platform 16 to a pre-determined position according to theparticular build menu 18 that is being used. In the instance of FIG. 10,the case 12 a has been moved completely across the row accumulatorplatform 16 at near its terminal or distal end. As noted previously,motor 78 is an encoder feedback motor under the control of controller14. The encoder feedback function allows the controller to recognize theposition of swing plate 24 along its travel path. Said another way, theposition of the swing plate 24 is electronically evaluated throughoutits travel path so that when the trailing edge 12″ of a case is in thedesired location on accumulator platform 16 according to the build menu18, the controller determines that the case is properly positioned andcase manipulator 10 motion is stopped.

FIG. 11 shows an alternative positioning for case 12 a on the rowaccumulator platform 16. Specifically, dictated by the build menu 18, inFIG. 11 the case 12 a has been positioned near the proximate end of therow accumulator platform 16.

Once a case 12 has been positioned on row accumulator platform 16 in thepre-determined position called for by build menu 18, paddle arm 40 ispivoted from the second position to the home position. This is shown inFIG. 12. Simultaneously, case 12 b is transported on infeed conveyer 100toward the location where the case 12 b may be moved onto the rowaccumulator platform with the case manipulator 10. It will beappreciated that with the swing plate 24 and paddle arm 40 both in thehome position of FIG. 12, the case manipulator may be moved back to itshome position as shown in FIG. 13 and the paddle arm 40 will notinterfere with the case 12 b as the swing plate 24 and the paddle arm 40move past the leading edge 12′ of case 12 b. This positioning with boththe swing plate 24 and paddle arm 40 in their home positions, and withthe trolley 62 positioned such that the paddle arm 40 may operate onanother case on infeed conveyer 100, the case manipulator 10 is in itshome position. In FIG. 13, the controller 14 has moved paddle arm 40into the pivoted, or second position (as shown by the arrow) so that itis adjacent to the side of case 12 b and the case manipulator 10 isready to move case 12 b.

In FIG. 14, case 12 b has been transported from the infeed conveyer 100by the pushing action of paddle arm 40 and onto row accumulator platform16. As the case 12 b is pushed onto the row accumulator platform, theleading edge 12′ of case 12 b abuts the trailing edge 12″ of adjacentcase 12 a. As such, both cases 12 a and 12 b are pushed along the rowaccumulator platform to the pre-determined and desired location.

FIG. 15 continues the sequence of figures from FIGS. 13 and 14. Thebuild menu 18 utilized for the arrangement of cases 12 a, 12 b and 12 cshown in FIG. 15 calls for the three cases to be arranged side by sideas shown in FIG. 18. Thus, in FIG. 15 the third case 12 c has beenpushed onto the row accumulator platform with the pushing action ofpaddle arm 40 so that the three cases are arranged in a row. At thistime, paddle arm 40 is pivoted to its home position. Once paddle arm 40is in the home position, and with swing plate 24 in its home position,row accumulator platform 16 with the row of cases defined by side byside cases 12 a, 12 b and 12 c, is moved vertically as shown by thearrow in FIG. 16 so that the row may be transferred to layer head 502 asdescribed above. As noted above, when the swing plate and paddle arm arein their home positions they are spaced from the adjacent edge of therow accumulator platform. Because the swing plate and paddle arm areboth in their home positions and separated from the edge of the rowaccumulator platform, the row accumulator platform is thus free to movevertically past the swing plate and paddle arm without interference andwithout regard to the position of the trolley 62 relative to the rowaccumulator. Said another way, regardless of the position of thetrolley, the row accumulator is capable of moving vertically past theswing plate and the paddle arm so long as both are in their homepositions. Simultaneously, or as quickly as possible after the row ofcases has been assembled on the row accumulator, the trolley 62 isshuttled to its home position—in the direction to the right in FIG.16—so that the paddle arm may be pivoted into the second position, readyto act on the next case 12 that has been delivered to the end of theinfeed conveyer 100 to begin building the next row. Some build patterns18 may call for a single case located at the furthest end of the rowaccumulator; the capability to move the row accumulator vertically (oralternately, to use a pick and place engagement of the cases) prior tothe full return of the trolley to its home position increasesefficiency.

FIGS. 17 through 25 continue with illustrations of sequential operationof case manipulator 10, but these figures show a second case 12positioning capability of the case manipulator over the pushingfunctions shown in FIGS. 9 through 16; namely, rotation of the case.Thus, when the build menu 18 calls for a case 12 to be rotated thecontroller 14 causes swing plate 24, in combination with paddle arm 40,to rotate the case.

It will be appreciated that when cases 12 are transferred from infeedconveyer 100 onto row accumulator platform 16 as shown in FIGS. 9through 16, it is the paddle arm 40 that is the component of casemanipulator 10 that defines the pushing member. However, when a case isrotated by case manipulator 10 as described below and as shown in FIGS.17 through 25, it is the swing plate 24 that is the component of casemanipulator 10 that defines the pushing member. The axis of pivotalrotation of swing plate 24 on vertical shaft 26 is perpendicular to theaxis of pivotal rotation of paddle arm 40 on shaft 44. This relationshipallows both the paddle arm 40 and the swing plate 24 to be the pushingmember depending on the positioning of the paddle arm and the swingplate.

Beginning with FIG. 17 it may be seen that paddle arm 40 is in thesecond position and that swing plate 24 also has been pivoted into thepivoted, second position where the swing plate. When a case 12 is to berotated as shown in FIG. 17, the case is initially engaged by casemanipulator 10 in the position shown in, for example, FIG. 9, withpaddle arm 40 in the second position to engage the side of the case.However, rather than the case manipulator 10 pushing the case 12laterally onto the row accumulation platform 16 as shown in FIG. 10, theswing plate 24 is pivoted by rotation of shaft 28 as shown with thearrow in FIG. 17. The paddle arm 40 is abutting the side edge of case 12and as swing plate 24 pivots from the home position to the secondposition the paddle arm 40 essentially captures the case between thepaddle arm and the swing plate so that the case rotates about a verticalaxis, perpendicular to the ground plane. The swing plate 24 rotates 90degrees so that the case 12 is rotated 90 degrees. When this happens,the leading edge 12′ of case 12 a is reversed. In other words, theleading edge 12′ of case 12 a prior to its rotation by case manipulator10 was the leading edge when the case was on the infeed conveyer, asdetailed in, for example, FIG. 9. However, after rotation that formerleading edge 12′ has now become the trailing edge 12″ by virtue of thenew orientation of the case on the accumulator platform 16.

FIG. 18 shows the next operation—shuttling of the case manipulator 10 inthe direction shown with the arrow to transfer the now-rotated case 12 ainto a pre-determined position on row accumulator platform 16 accordingto the build menu 18. As the case manipulator 10 is shuttled the swingplate 24 pushes on the trailing edge 12″ of the case—the paddle arm 40retains the case in a correct position relative to the swing plate. Withreference to FIG. 19, once case 12 a is in the desired location on rowaccumulator platform 16 the paddle arm 40 and swing plate 24 aresimultaneously (or sequentially) pivoted from their second positions totheir home positions and the case manipulator 10 is shuttled back to itshome position as shown by the arrow in FIG. 19. At the same time, case12 b is being moved into position on the infeed conveyer 100 to beoperated upon by case manipulator 10, that is, with the leading edge ofthe case abutting backstop bar 20. The rotation of case 12 b is thencommenced in the same manner as described above with case 12 a as shownin FIGS. 20 and 21. Depending on the build menu, the second case 12 bmay be moved into an abutting relationship with the first case 12 a asshown in FIG. 22, or the build menu may call for a space between cases12 a and 12 b as shown in FIG. 21.

FIGS. 23 and 24 illustrate the pivoting of paddle arm 40 from its secondposition (FIG. 23) and swing plate 24 to its second position (FIG. 24)after case 12 b has been pushed into the pre-determined position onaccumulator platform 16.

With the row of cases assembled on accumulator platform 16, as shown inFIG. 24, the case manipulator 10 is shuttled back to its home position.In FIG. 25 the row accumulator 16 is being lifted upwardly with thecomplete row of cases, 12 a and 12 b, for downstream processing andtransfer to the layer head 502 in the same manner as detailed above.

The drawing figures described above illustrate the case manipulator 10operating on a single case 12 at a time as the case is delivered on theinfeed conveyer 100. In the instance of the cases 12 shown in thedrawings, the case is relatively large in size and as such a row ofcases comprises plural single cases aligned side-by-side into a row asshown in, for example, FIG. 16. But those of skill in the art willunderstand that the case manipulator 10 of the invention is capable ofoperating on more than one case at a time, for example, when theindividual cases are smaller in size than those shown in the drawings.To illustrate the point, assume that the cases have a length dimensionthat is ¼ of the length of the cases 12 shown in the drawings of FIGS. 1through 25. In that situation, the paddle arm 40 when it is in thepivoted position extends along the sides of 4 cases rather than one. Thefour cases are thus pushed onto the row accumulator platform 16 in agroup. The same basic processing continues as described above, includingturning 4 of these smaller sized cases at one time with the combinedaction of the paddle arm 40 and swing plate 24 as detailed above,according to the build menu 18 that is specific for the smaller-sizedcases. The ability of case manipulator 10 to manipulate more than one,smaller sized case at one time is illustrated schematically in FIG. 2with the smaller cases 12 x and 12 y shown in stack 506.

As noted above, as an alternative to the vertically movable rowaccumulator 16 it is possible to transfer a row of cases 12 that hasbeen assembled on the row accumulator using a pick and place clampassembly. One embodiment of a pick and place apparatus 200 that may beused in conjunction with a case manipulator 10 according to the presentinvention is shown in isolation in FIG. 26—in FIG. 26 the casemanipulator 10 is not shown in order to illustrate better the componentsof the apparatus 200. A row of cases 12 a through 12 d have beenassembled on a row build platform 202 utilizing a case manipulator 10according to the present invention. The row build platform 202 in theillustration of FIG. 26 is a roller conveyer deck defined by pluralrollers. The pick and place apparatus 200 is best seen in the side viewof FIG. 27 and is defined by a lower support plate 204 and an upperclamp arm 206, both of which are carried on a carriage 208 that allowsfor both vertical movement (arrow A) and horizontal movement (arrow B).The support plate 204 is also horizontally moveable along the arrow Bdirection. In operation, when a complete row of cases has been assembledon the row build platform 202 according to the build menu 18 thecarriage 208 is operated so that the support plate 204 is positionedadjacent the bottom edges of the assembled cases. An end retaining bar210 is positioned along the downstream edge of the case 12 a. With theupper clamp arm 206 in an upper position (as shown in FIG. 27) thesupport plate 204 is moved horizontally (arrow B) so that the plate ispositioned beneath the bottoms of the aligned cases and the upper clamparm 206 is moved downwardly (arrow A) against the cases to thereby clampthe entire row onto the support plate 204. At this point the carriage208 is moved vertically to move the entire clamped row with it, and thenhorizontally to place the row on a pallet or stack of cases. Thismovement of the carriage 208 is shown in FIG. 28. Once the carriage isin the desired location for depositing the row on the pallet the upperclamp arm 206 is moved vertically to release pressure on the cases 12and the support plate 204 is withdrawn from beneath the row of cases tothereby deposit the cases as desired.

In yet another alternative embodiment of a pick and place system, a pairof clamp bars moves over the assembled row of cases with the opposedclamps opened so that they cases fit between the bars. The clamp barsare lowered over the cases and moved inwardly toward one another tocapture the cases between the bars. The clamped cases are then liftedupwardly off the row accumulator platform 16 and transferred to a palletor a stack of cases already assembled on a pallet. It will beappreciated that by positioning both the swing plate 24 and the paddlearm 40 in their home positions (as shown, for example, in FIG. 19), andpick and place clamp bar transport system is capable of being loweredover a row of cases to clamp the row regardless of the position of thetrolley 62 relative to the row accumulator platform 16.

In yet another embodiment according to the present invention it ispossible to eliminate the paddle arm 40 with a vacuum pad shownschematically in FIG. 7 with phantom lines and identified with referencenumber 110. The vacuum pad 110 is connected to a vacuum source 112 sothat cases may be retained against the major surface 38 as they aremanipulated by the movement of the swing plate. More specifically, usingthe engagement of a case 12 to the swing plate 24 equipped with vacuumpad 110 the trolley 62 may “grip” the case from the infeed conveyer,shuttle the case onto the row build accumulator 16, and rotate the caseby 90 degrees as described above but without the paddle arm 40.

Turning now to the palletizer 300 shown in FIGS. 29 and 30, the rowaccumulator platform 16 is stationary and located at an elevatedposition. A vertically movable layer head 302 is, in the view of FIG.29, at a position that the layer head is coincident with, or slightlylower than, the elevation of the row accumulator platform 16 so that arow of cases 12 assembled on the row accumulator platform may be pushedby a pusher bar onto the layer head. The carriage assembly 60, trolley62 and thus swing plate 24 and paddle arm 40 are also positioned at anelevated level adjacent the row accumulator platform 16 so that theswing plate 24 and paddle arm 40 may manipulate cases 12 as described indetail above. The infeed conveyer 100 is not shown in FIGS. 29 and 30but it may be seen that it also is at the elevated position as shown bycases 12 f and 12 g which are at the level of the infeed conveyer 100.

In FIG. 29 the case manipulator 10 is in the home position, the swingplate 24 is in the pivoted position and the paddle arm 40 is in a homeposition—the trolley 62 is ready to push the case 12 e onto the rowbuild accumulator 16. A row of cases, 12 a through 12 d, has alreadybeen pushed onto the layer head 302 by pusher arm 304—the assembled rowof cases is pushed from the row accumulator platform 16 across a narrowgap 306 onto the layer head. The gap 306 is needed for a plate post 308.

In FIG. 30 the trolley 62 has been shuttled from the home position tomove case 12 e onto the desired position on row accumulator platform 16.The next following case 12 f on infeed conveyer 100 is ready to be movedto the distal end of the infeed conveyer and the case manipulator 10will simultaneously be shuttled back to its home position (with theswing plate 24 and paddle arm 40 being moved to their home positions sothat they do not interfere with case 12 f as the trolley 62 moves theswing plate past case 12 f). It will be appreciated that when a completelayer has been assembled on the layer head 302 the layer head is movedvertically downward to deposit the full layer on the pallet or on thestack that is being built.

The foregoing system and methods allow for accurate positioning of acase on the row accumulator platform 16 before the next case 12 isinduced onto the row build accumulator. In some instances the build menu18 will call for the next case 12 b to be immediately adjacent the priorcase 12 a so that there is no gap between the two cases 12 a and 12 b.In other instances, the build menu 18 will call for a gap between thecases. In the latter case where a gap is required the gap is created byceasing motion of the case manipulator 10 when the system recognizes thetrailing edge 12″ to be in the desired position according to the buildmenu.

While the present invention has been described in terms of preferred andillustrated embodiments, it will be appreciated by those of ordinaryskill that the spirit and scope of the invention is not limited to thoseembodiments, but extend to the various modifications and equivalents asdefined in the appended claims.

The invention claimed is:
 1. A palletizer item row building apparatusfor arranging items into rows, each item having a trailing edge and aleading edge, comprising: an infeed conveyer for delivering items at afirst level and in a first orientation; a row accumulator having a rowbuild surface and the row accumulator defining a longitudinal axis; anitem manipulator adapted for receiving an item from the infeed conveyerand for positioning the item on the row accumulator, the itemmanipulator comprising: a carriage mounted on a linear track and adaptedfor reciprocating linear movement along the longitudinal axis; an itemturner movable from a first position to a second position, the itemturner defined by a stop that is pivotally mounted for movement about anitem turner axis and an arm that is movable between a first position inwhich the arm is separated from the row accumulator and a secondposition in which the arm extends over the row accumulator, wherein whenthe item turner moves from the first position to the second position anitem received by the item turner is moved from the first orientation toa second orientation; and a trailing edge detector which determines theposition of the trailing edge of the item; and a controller associatedwith the encoder of the item manipulator which associates the positionof the item manipulator with the position of the item.
 2. The item rowbuilding apparatus according to claim 1 including a motor for moving thecarriage and wherein the trailing edge detector further comprises anencoder in the motor.
 3. The item row building apparatus according toclaim 2 in which the encoder determines the position of the first plate.4. The item row building apparatus according to claim 2 in which theencoder determines the position of the item turner.
 5. The item rowbuilding apparatus according to claim 1 in which the item turner isfurther defined by a swing plate mounted to the carriage at a pivot thatdefines the item turner axis, the swing plate pivotally mounted formovement on the pivot about the item turner axis between a firstposition in which the swing plate is separated from the row accumulatorand a second position in which the swing plate extends over the rowbuild surface.
 6. The item row building apparatus according to claim 5in which the item manipulator is further defined by a paddle arm mountedto the swing plate on a paddle arm pivot defining a paddle arm axis thatis transverse to the swing plate axis, the paddle arm pivotally mountedfor movement of the pivot arm about the paddle arm axis between a firstposition in which the paddle arm is separated from the row accumulatorand a second position in which the paddle arm extends over the row buildsurface.
 7. The row building apparatus according to claim 6 in which thecarriage is movable from a first position to a second position and whenthe carriage is in the first position and the paddle arm is in thesecond position the paddle arm is adapted for engaging an item on theinfeed conveyer.
 8. A method of orienting items in rows in a palletizer,each item having a leading edge and a trailing edge, comprising thesteps of: a. delivering at least a first item to a stop position on aninfeed conveyer; b. confirming a first orientation of the first item inthe stop position; c. determining if the first item requiresreorientation from the first orientation to a second orientation; d. ifthe first item requires reorientation, causing the first item to bereoriented from the first orientation to the second orientation with anitem turner and delivering the reoriented first item from the infeedconveyer to a row build conveyer; e. if the first item does not requirereorientation, delivering the first item from the infeed conveyer to therow build conveyer with the item turner; and f. in steps d. and e.,determining the position of the trailing edge of the item with adetermined position of the item turner.
 9. The method according to claim8 wherein the reorientation of step d. comprises rotating the item by 90degrees.
 10. The method according to claim 8 wherein the methodcomprises orienting plural items simultaneously and the reorientation ofstep d. comprises rotating plural items simultaneously by 90 degrees.11. The method according to claim 8 including the step of moving thefirst item on the row build conveyer to a predetermined positionaccording to a row build menu.
 12. The method according to claim 11including the step of detecting the location of the trailing edge inorder to determine the position to which the first item is delivered tothe row build conveyer.
 13. The method according to claim 12 includingdelivering the item to the row build conveyer with a plate that isdriven by a motor and detecting the location of the trailing edge withan encoder in the motor.
 14. A method of orienting items for buildingrows of items in a palletizer, comprising the steps of: a. delivering anitem in a first orientation on an infeed conveyer; b. determining if thefirst orientation matches a first item predetermined orientationaccording to a row build menu; c. determining if the first item requiresreorientation to match the first item predetermined orientationaccording to the row build menu; d. if the first item requiresreorientation to match the first item predetermined orientation, causingthe first item to be reoriented from the first orientation to a secondorientation with an item turner and delivering the reoriented first itemto a row build conveyer; e. if the first item does not requirereorientation, delivering the first item to the row build conveyer withthe item turner; and f. in steps d. and e., determining the position ofthe trailing edge of first item with a determined position of the itemturner.
 15. The method according to claim 14 including the steps of: a.delivering a second item in a first orientation on the infeed conveyer;b. determining if the first orientation of the second item matches asecond item predetermined orientation according to the row build menu;c. if the second item requires reorientation to match the second itempredetermined orientation, causing the second item to be reoriented fromthe first orientation to a second orientation and delivering the seconditem to the row build conveyer in a predetermined location relative tothe first item on the row build conveyer; d. if the second item does notrequire reorientation, delivering the second item to the row buildconveyer in a predetermined location relative to the first item on therow build conveyer; and in steps c. and d., determining the position ofthe trailing edge of first item with a determined position of the itemturner.
 16. The method according to claim 15 including a delivering thefirst item to the row build conveyer with a motor driving the itemturner and wherein the location of the trailing edge of the first itemon the row build conveyer is detected by an encoder in the motor. 17.The method according to claim 16 including the step of delivering thesecond item to the row build conveyer in a desired position relative tothe first item according to a row build menu.
 18. The method accordingto claim 17 in which a leading edge of the second item abuts thetrailing edge of the first item when the second item is delivered to therow build conveyer in the desired position of the second item relativeto the first item.
 19. The method according to claim 17 in which aleading edge of the second item is spaced apart from the trailing edgeof the first item when the second item is delivered to the row buildconveyer in the desired position of the second item relative to thefirst item.